Probability characteristics of thermal infrared radiation for anisotropic spheres

Abstract

In accordance with the hot issues of infrared detection and guidance,an IR transmission process from target to sensitive array w as established to explore the IR signatures of an anisotropic-isothermal sphere model. The energy probability density distribution function w as employed to describe the energy intensity levels of sensitive array units. The energy distributions of detector units w ere abtained w ith the aid of the Monte Carlo Method. The relationship betw een target directional IR radiation characteristics and energy distributions on the sensitive array w as revealed. It indicates that in the case of the equal hemispherical emissivity of far-field small targets,increasing the emissivity in the near-normal direction can appreciably enhance the IR intensity of the image-center unit and improve the IR intensity contrast among the image units.